Tooth adapters are commonly used to detachably mount a digging tooth or tip to a bucket or similar implement. Such tooth adapters are carried on the base edge of the bucket. In the past, tooth adapters were simply welded to the base edge of the bucket. While the use of welding as an attachment mechanism was effective, such welding made the replacement of the adapter difficult and time consuming. More recently, various ways of mechanically attaching such adapters have been employed in order to reduce the time and costs of replacing tooth adapters when they either break or become worn out. One of such ways is where the adapter is bolted to the base edge of a bucket. However, it is frequently difficult to remove the bolts after normal use because of the wearing away of the bolt head. Additionally, as the components increase in size, it is more difficult to get bolts large enough and/or to apply sufficient torque to properly tighten the bolts. Furthermore, the bottom of the bucket is subject to high wear. As a consequence, the nut and bolt-end are prematurely worn away, allowing the adapter to come loose and fall off.
In other type of attachment system, a C-shaped clamp member is vertically inserted through slots in upper and lower straps of an adapter and through a similar slot in the base edge. Such C-clamp is held in place by hammering a wedge in-between the C-clamp and edge of the slot in the base edge. In view of the size of the components used on very large buckets, a large amount of effort must be expended in hammering the wedge. Also, the wedges may become loose prematurely, resulting in the adapter falling off the bucket, or the wedge may become very difficult to remove due to corrosion or dirt impacting around the components, requiring the adapter to cut off with an oxy-acetylene torch.
To eliminate the need for hammering one wedge against another wedge, others have employed a bolt as a tensioning device in a wedge type retainer to draw and secure the wedges together. One such device is disclosed in U.S. Pat. No. 5,410,826 issued May 2, 1995 to Darryl R. Immel et. al. Another such device is disclosed in U.S. Pat. No. 4,433,496 issued Feb. 28, 1984 to Larren F. Jones et. al. that employs an arcuate camming wedge. In both such attempts however, the tensioning bolt is coupled between the two wedge members. Because of the lateral shifting of the wedges as they are drawn together, a bending force is exerted on the bolt or the bolt head is caused to be tightened against a surface that is cocked relative to the head. Such conditions may result in the loosening of the bolt during use and the subsequent loss of the retaining device and the adapter.
The present invention is directed to overcoming one or more of the problems as set forth above.